#!/bin/sh
#
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. /usr/local/share/bastille/common.sh
. /usr/local/etc/bastille/bastille.conf

usage() {
    error_exit "Usage: bastille rdr TARGET [clear] | [list] | [tcp <host_port> <jail_port>] | [udp <host_port> <jail_port>]"
}

# Handle special-case commands first.
case "$1" in
help|-h|--help)
    usage
    ;;
esac

if [ $# -lt 2 ]; then
    usage
fi

TARGET="${1}"
shift

# Can only redirect to single jail
if [ "${TARGET}" = 'ALL' ]; then
    error_exit "Can only redirect to a single jail."
fi

# Check jail name valid
JAIL_NAME=$(jls -j "${TARGET}" name 2>/dev/null)
if [ -z "${JAIL_NAME}" ]; then
    error_exit "Jail not found: ${TARGET}"
fi

# Check jail ip4 address valid
JAIL_IP=$(jls -j "${TARGET}" ip4.addr 2>/dev/null)
if [ -z "${JAIL_IP}" -o "${JAIL_IP}" = "-" ]; then
    error_exit "Jail IP not found: ${TARGET}"
fi

# Check rdr-anchor is setup in pf.conf
if ! (pfctl -sn | grep rdr-anchor | grep 'rdr/\*' >/dev/null); then
    error_exit "rdr-anchor not found in pf.conf"
fi

# Check ext_if is setup in pf.conf
EXT_IF=$(grep '^[[:space:]]*ext_if[[:space:]]*=' /etc/pf.conf)
if [ -z "${JAIL_NAME}" ]; then
    error_exit "ext_if not defined in pf.conf"
fi

while [ $# -gt 0 ]; do
    case "$1" in
        list)
            pfctl -a "rdr/${JAIL_NAME}" -Psn 2>/dev/null
            shift
            ;;
        clear)
            pfctl -a "rdr/${JAIL_NAME}" -Fn
            shift
            ;;
        tcp)
            if [ $# -lt 3 ]; then
                usage
            fi
            ( pfctl -a "rdr/${JAIL_NAME}" -Psn;
              printf '%s\nrdr on $ext_if inet proto tcp to port %s -> %s port %s\n' "$EXT_IF" "$2" "$JAIL_IP" "$3" ) \
                  | pfctl -a "rdr/${JAIL_NAME}" -f-
            shift 3
            ;;
        udp)
            if [ $# -lt 3 ]; then
                usage
            fi
            ( pfctl -a "rdr/${JAIL_NAME}" -Psn;
              printf '%s\nrdr on $ext_if inet proto udp to port %s -> %s port %s\n' "$EXT_IF" "$2" "$JAIL_IP" "$3" ) \
                  | pfctl -a "rdr/${JAIL_NAME}" -f-
            shift 3
            ;;
        *)
            usage
            ;;
    esac
done